Taenidium barretti ichnofabric and rainfall seasonality:Insights into dryland suites of Scoyenia ichnofacies  

作　　者：Diego Luciano Nascimento Renata Guimaraes Netto Alessandro Batezelli Francisco Sergio Bernardes Ladeira Daniel Sedorko 

机构地区：[1]ICHNOS Research Group,Geology Graduate Program,Unisinos University,Av.Unisinos,950,10 Sao Leopoldo,RS,93022-750,Brazil [2]Campinas State University,Geology and Natural Resources Department,Zeferino Vaz University City,Barao Geraldo,Campinas,SP,13083-970,Brazil [3]Laboratory of Pedology(LABPED),Department of Geography,Geosciences Institute,Geosciences,State University of Campinas,Campinas,SP,13083-855,Brazil [4]Museu Nacional,Departamento de Geologia e Paleontologia,Universidade Federal do Rio de Janeiro.Horto Botanico,Parque Quinta da Boa Vista,R.Gen.Herculano Gomes,1340,Sao Cristovao,Rio de Janeiro,RJ,20940-040,Brazil

出　　处：《Journal of Palaeogeography》2023年第1期28-49,共22页古地理学报（英文版）

基　　金：the Sao Paulo Research Foundation(FAPESP)for supporting and funding this work(grant 2015/17632-5);The Brazilian National Council for Scientific and Technological Development(CNPq)is also thanked for the Ph.D.grant provided to DLN(140807/2017-9);the post-doctoral fellowship grant to DS(159548/2018-7);the research grants to AB(310734/2020-7);RGN(310377/2019-6);FSBL(307951/2018-9,303977/2021-3).

摘　　要：The present work analyzes the monotypic Taenidium barretti ichnofabric developed in abandoned channels and floodplains to understand its paleoecological significance in highly seasonal fluvial systems.The data come from the Cretaceous paleosols of the Marília Formation(Bauru Basin,SE Brazil),in which the T.barretti ichnofabric and rhizoliths represent the biotic record.Beetle larvae are considered to be the most likely T.barretti tracemakers in these paleosols.The intensity and recurrence of bioturbation suggest that the windows of opportunity for beetle population growth were very short and controlled by the progressive substrate desiccation after flood cessation.The characteristics of the trace fossil assemblage suggest soil colonization by r-strategic organisms triggered by flooding events that provided the resource inputs necessary for their living during rainy seasons.The results also show that in fluvial systems with high discharge variations,the boundaries between a“pre-desiccation suite”and a“desiccation suite”in the Scoyenia ichnofacies can be diffuse due to the short duration of colonization windows and progressive terrestrialization of floodplains and channels.Therefore,the frequency of flooding events,the lowered water table,and the rapidity of substrate desiccation constrained colonization by other burrowers and may be considered as firstorder factors controlling the generation of a monotypic T.barretti ichnofabric.Thus,the monotypic Taenidium ichnofabric in the Scoyenia ichnofacies context is an ichnomarker of brief windows for colonization in highly seasonal environments.

关 键 词：ICHNOLOGY PALEOPEDOLOGY Continental ichnofacies Meniscate burrows ICHNOFABRIC 

分 类 号：Q915[天文地球—古生物学与地层学]